Insulin sensitivity increase after calcium supplementation and change in intraplatelet calcium and sodium-hydrogen exchange in hypertensive patients with Type 2 diabetes

Research output: Contribution to journalArticle

Abstract

To investigate the effect of oral calcium (Ca2+) supplementation on insulin sensitivity measured by the euglycaemic hyperinsulinaemic clamp, intraplatelet cationic concentration of Ca2+ ([Ca2+](i)) and the transmembrane sodium-hydrogen exchanger (NHE) activity in erythrocytes in subjects with Type 2 diabetes and hypertension. In this parallel randomized controlled single-blinded trial, 31 patients were allocated to receive either 1500 mg of Ca2+ orally, daily (n = 15) or no treatment (n = 16) for 8 weeks. At baseline and at the end of the 8-week period insulin sensitivity, [Ca2+](i) and the first isoform of NHE (NHE-1) activity were measured. At the end of the study, subjects who received Ca2+ supplementation showed higher insulin sensitivity (Delta M-value 0.32 +/- 0.5 mmol/min P < 0.05) and lower [Ca2+](i) (125.0 +/- 24.7 to 80.4 +/- 10.6 nmol/l, P < 0.05, mean +/- sem) and NHE-1 activity (79.5 +/- 10.0 to 52.1 +/- 6.4 mmol Na/l red cell/h, P < 0.05). None of the above parameters were changed in the control group. Simple regression analysis demonstrated the change in [Ca2+](i) significantly determined insulin sensitivity change (beta = -0.36, P < 0.05). Oral Ca2+ supplementation improves insulin sensitivity in patients with Type 2 diabetes and hypertension. These changes are likely to be mediated by changes in intracellular ionic Ca2+. NHE-1 activity was also reduced after Ca2+ supplementation but its role in insulin sensitivity requires further investigation.

Details

Authors
  • M. I. Pikilidou
  • A. N. Lasaridis
  • P. A. Sarafidis
  • C. D. Befani
  • G. G. Koliakos
  • I. M. Tziolas
  • K. A. Kazakos
  • J. G. Yovos
  • Peter Nilsson
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Endocrinology and Diabetes

Keywords

  • calcium supplementation, hyperinsulinaemic clamp, insulin sensitivity
Original languageEnglish
Pages (from-to)211-219
JournalDiabetic Medicine
Volume26
Issue number3
Publication statusPublished - 2009
Publication categoryResearch
Peer-reviewedYes